Paving stripping apparatus



Nov. 6, 1945. H. E. BAKER 2,388,461

PAVING STRIPPING APPARATUS Filed July 4, 1944 2 Sheets-Sheet 1 I8 54- 28 2 T 50 I 25 \lb 0 "o 32 v 22 v 38 m l0 (0* Nov. 6, 1945. H. E. BAKER PAVING" STRIPPING APPARATUS Filed July 4, 1944 2 Sheets-Sheet 2 IN VEN TOR.

Patented Nov. 6, 1945 UNITED STATES PATENT OFFICE 2,388,461

PAVING STRIPPING APPARATUS Henry E.1Baker, Milton, Mass. Application July 4, 1944, Serial No. 543,482

Claims.

This invention relates to animproved method of stripping surface layers from paved streets and the like, and to apparatus for practicing the same. More particularly, it provides a method and apparatus for stripping one or more paving layers from a street or road without disruption of the base or bed and at a speed greatly exceeding what has been possible according to prior methods and with heretofore available apparatus.

The re-surfacing of a paved street or road involves the removal of the old surface layer or layers whether it is of sheet paving material such as asphalt or bituminous macadam, or is a block pavement of which vitrified brick, wood block and granite block are examples. However, the base orbed on which the wearing surface layer or layers are supported ordinarily is in good condition and entirely suitable for receiving the new wearing surface provided the old wearing surface can be stripped away Without disturbing the base or bed.

Heretofore, it has been customary to break up the surface layer which is to be removed by any of various power devices, after which the broken surface material is removed by any suitable means. It has not been practicable to employ power shovels for removing the broken surface. In fact it has been customary in road resurfacing specifications to exclude the use of power shovels because experience has taught that their use necessarily disrupts and disturbs the base or bed. In consequence, the stripping away of a worn surface layer has been time consuming, expensive and laborious.-

Itis an object of my present invention to simplify the procedure of stripping the worn surin design and layer and the base or bed, after which the stripper boom is elevated to lift the surface layer in sizeable sheet form away from the base. Then a combined upward movement and movement toward the sheet increases the bite and the sheet ultimately breaks as the movement toward the sheet continues and finally topples the sheet over upon the adjacent surface. If the sheet is in the way, it may be kicked by the heel of the stripper onto the stripped base or bed, to be removed to a truck or the like.

A feature is to provide a stripper means on the stripper boom which is relatively short from the tips of the prongs to its heel thereby to minimize any tendency for the heel to dig into the base during a stripping operation.

A further feature is to provide the stripper means with a clear space through which a stripped sheet may swing as it is lifted and swung preparatory to its ultimate toppling over onto the adjacent surface.

It is, moreover, my purpose and object generally to improve upon prior methods and appa ratus for stripping surface layers from paved streets and the like.

In the accompanying drawings:

Figure 1 is a more or less diagrammatic view in side elevation of a conventional power pull shovel rig having my stripper boom substituted therein for the regular shovel-carrying dipper stick;

Figure 2 is a fragmentary elevation of the stripper means, on a larger scale, shown taking a bite between an exposed edge of the surface layer to be stripped from the supporting base;

Figure 3 is a view similar to Figure 2 but showing the stripper means after it has been initially elevated and showing the engaged edge of the surface layer pulled away from the base;

Figures 4 and 5 are views similar to Figures 2 and 3 but showing the stripper means in successively later positions during its travel for stripping a sheet section from the base;

Figure 6 is a view similar to Figures 2-5 showing the stripper means beyond the folded over sheet section in position to kick the sheet section onto the base or sub-grade;

Figure 7 is a plan view of the stripper means, with the stripper boom shown in cross-section; and

Figures 8, 9 and 10 are fragmentary views of the stripper means of Figure 7, showing it respectively in side, rear and front elevations.

Referring to the drawings, a conventional power pull shovel rig is represented diagrammatically in Fig. 1 equipped with my improved stripper boom ill in place of the usual dipper stick which ordinarily carries the relatively large and heavy 2 shovel. The rig as shown comprises a caterpillar type of vehicle l2 on which is mounted the operators cabin M from which the main boom l6 and the stripper boom in may be controlled and manipulated by means of the control cables [8 and 20. The cabin I4 is suitably mounted in the usual manner so that it and the booms l6 and I may be rotated on the vehicle l2.

My improved stripper boom ID will be generally the same for any of the various'makes of power pull shovel rigs. However, .since each make of pull shovel has specific features different from each other, including differences in the manner of attachment and control of its dipper stick, my stripper boom ID for any particular make of power pull shovel rig will be designed with the specific attachment and control connec tions adapting it for taking the placeofa'particular make of dipper stick. Hence, in Fig. .1, the stripper boom I0 is designed for embodiment in one commercial make of power pull-shovel rig in which the stripper boom I'O is:pivotally-mounted at 22 at the outer end of'the'main boom 16 andprojects above boomlB. :A yokeiZi is pivotally mounted at 526 at the upper end "of stripper boom I'D, the yoke having a sheaVe Z-S rotatable therein at its end toward the cabin 14. Another sheave 33 is meuntediat the upper end of .an upright 32 rigid on the'cabin platform, and the control cable 18 has one end secured at '34 to yoke 24 and extending aroundsheave 30,'thence back to and around sheave-.28 andback a'gain to sheave whence it goes to a suitable winding drum or winch in the control cabin.

The other control cable 20 'has-its end connected at 36'to the stripper :boom lllitoward the free end of that boom and extends .thence over sheave 38 to a winding drum or winch indicated generally at 40.

The operator,-by drawing inor-lettingputon the respective cables I8, 20 CaIItCODtIOITthB POSltions of the booms-l6 and-l0.

The stripper boom t0 preferably comprises a rectangular "core of wood 42 which issubst-antially encased by the two.channeltirons fl with suitable bolts-securing the core'and channel irons together. At the free end of the stripper boom-1B, I provide a strong and durable but relatively light-weight strippenmeans whichrin general is rake-like in structure. As herein illustrated, it comprises a rectangular plate 46 rigidly secured to thefree end of stripper boom-l0 as by the angle irons48 on opposite sides of'the boom-l0, and thebracing. ribs 50; acting through plate :52 on that side: of the boom-l9 which is-towardthe teeth or prongs 54.

While I show three teeth-or pron-gsifi l, only two may suffice for some -work,.:-and more-than'three may be desirable under particular conditions. In the drawings, the teeth=54have suitable-ears 56 .by-which they may be.bolted, as at'58, to the under side of plate 46, projecting asubstantial distance beyond the plate in spacedtparallelism with eachother. The. end of- .each-toothi lpref erably isbevelled .on its upper sideas at 60, and the end of each, on the under side, may have-a slight bevel as at 62.

It willbe observed that theplate 4.6 has-little or no projection beyond the stripper boom on that side of the boom opposite the side Where teeth '54 project, and -this'region of nomprojection of'the plate conveniently may be'termed the "heel of the bOOm l0. Also,the undersides of the teeth 54 are in a lower plane than the under side of plate which,in'conjunction-with essential, according to my present invention, that the stripper means be always completely under the operators control so that the stripping may .be-accomplised without disturbing the sub-grade or base.

ReferringtoFig. 2, the sub-grade or base is indicated at 64 and the surface layer to be stripped is represented at 66, although it should be understoodthat the surface to be .removed may 'consist of a plurality'of paving layers, .or may be a block pavement,tin which latterrcase the blocks will be stripped off in-sizeable .sheets of blocks. Preferably an edge :of the layer to be stripped will be exposed by any suitable meanssothat the stripper. prongs ortteeth 54 maybe directed by the operator intoa bite" betweenthe exposed edge and the sub-grade or base 64. After a suitable bite is effected, the operator elevates the stripper boom If! approximately in a vertical direction, as in Fig. 3, which causesthe engaged edge of layer 65 to be lifted away from the base. The operator then pulls the stripper boom towardhim while continuing to elevate it, as suggested in Fig. 4, thereby to increase the bite of teeth 66 under the lifted sheet section and to initiate a'folding of the lifted sheet along atransverse foldlinersat '10 in Fig. 4, where the sheet will :start to break. .Continued movement of the stripper 'bOWaTdithGDDET- atorand also upward, swingsthesheetrsection, now broken at fold line-l0, substantiallyzasrepresented in Fig. 5, after which "further'movement toward the operator causeszthe-sheet'rsectionwo topple over upon the-adjacent paved ssurface, ras in Fig. 6. If thesectionis in the rwaygit may be kicked by 'the heel of the stripper, moved in the direction of the arrow in-Fig. 6, overaonto'thaalready strippedsub-grade 64.

It is important to note that the vehicle" I Z'stands on the paved street and the-surfacestripping is toward the vehicle'whichbacks along'theipaved street as the stripping proceeds, so that the stripped sub-grade can be undisturbed. The sizeable sheet sections 'thus quickly and efficiently stripped free of the base can be broken into smaller pieces, if desired, by the :heel of the stripper, and. the sections removed in any convenient manner.

Because no preliminary breaking of'the surface is required, and because the surface strips away from the subgrade inirelatively large sheet sections, my invention enables the stripping of a given areaof paved surface ina fraction of the time heretofore required and with .iess 'disturbance of the sub-gradev orbasethan'has-been customary with prior methodsand apparatus.

I claimas my invention:

1. In a paving stripper rig, a stripper boom 'having. rigidly secured .to its lower end a stripper plate having area several timesgreater than the crosssectional area of the stripper boom and disposed flatwise directly against the end of the boom approximately in right angular relation to-the axis of said boom, said plate'having relatively large projection outward from the boom on three sides including the side toward said rig and there being spaced projections on the plate at its edge which is toward said rig, whereby said projections and plate can engage deeply under a section of pavement which is to be stripped from a road bed, and a said section of pavement lifted by said plate can have relatively large integral lateral extent at opposite sides of the plate.

2. In a paving stripper rig, a stripper boom having rigidly secured to its lower end a lightweight stripper means comprising a plate disposed flatwise of and approximately in the plane of the end of said boom and with the end of the boom entirely within the confines of the plate, generally plane stripper elements disposed in spaced parallelism on and projecting from the plate in generally right angular relation to the axis of said boom, said stripper elements having plane upper and lower surfaces and having their free ends projected outward beyond said boom a distance at least twice the cross-sectional dimension of the boom in the corresponding direction, and distributed laterally through a distance at least three times the cross-sectional dimension of the boom in the corresponding direction.

3. In a paving stripper rig, a stripper boom having rigidly secured to its lower end a lightweight stripper means comprising a stiff relatively light plate having area several times the cross-sectional area of the boom and disposed generally in right angular relation to the axis of the boom and projecting appreciably beyond the boom at only three sides, and stripper elements projecting beyond said plate in parallelism with the plane of the plate on that side which is toward the rig, the free ends of said elements being outward beyond the boom a distance at least twice the cross-sectional dimension of the boom in the corresponding direction.

side remote from the rig,

4. In a paving stripper rig, a stripper boom having rigidly secured to its lower end a lightweight stripper means comprising a plane plate having area several times greater than the crosssectional area of the boom and disposed approximately in the plane of the end of the boom and approximately in right angular relation to the axis of the boom, said plate having relatively large projection outward from the boom on three sides including the side toward the said rig, and being free from appreciable projection on the there being spaced projections on the plate at its edge which is toward the rig, and a broad vertically and laterally extending element at said remote side of said plate constituting a pusher and, in conjunction with the adjacent edge of the plate constituting a heel for breaking stripped sections of pavement and kicking sections and fragments to clear the way for a fresh stripping bite of the plate.

5. A paving stripper for paved streets and the like comprising a vehicle having a main boom pivotally mounted thereon for movement about its pivot in a vertical plane, a stripper boom pivotally mounted on the main boom and swingable in a vertical plane, said stripper boom having directly secured thereon at its lower end a plate exceeding in area by several times the crosssectional area of the stripper boom and rigidly fixed in approximately right angular relation to the axis of the stripper boom, said plate being positioned with relatively large projecting extent at three sides of the stripper boom including the side which is toward the vehicle, and having a plurality of spaced stripper elements projecting a substantial distance outward from said plate on the said side which is toward the vehicle.

HENRY E. BAKER. 

